<template>
  <div>
    <span>全选:</span>
    <input type="checkbox" v-model="isCheckAll"/>
    <button @click="reverse">反选</button>
    <ul>
      <li v-for="(item,index) in arr" :key="index">
        <input type="checkbox" v-model="item.c"/>
        <span>{{item.name}}</span>
      </li>
    </ul>
  </div>
</template>

<script>
export default {
  computed: {
    isCheckAll: {
      get() {
        return this.arr.every(item=> item.c == true)
      },
      set(newValue) {
      this.arr.forEach(item => {
        item.c = newValue
      })
    }
    },
   
    // isCheckAll() {
    //   return this.arr.every(item=> item.c == true)
    // }
  },
  data() {
    return {
      arr: [
        {
          name: "猪八戒",
          c: false,
        },
        {
          name: "孙悟空",
          c: false,
        },
        {
          name: "唐僧",
          c: false,
        },
        {
          name: "白龙马",
          c: false,
        },
      ],
    };
  },
  methods: {
    reverse() {
      this.arr.forEach(item => {
        item.c = !item.c
      })
    }
  }
};
</script>

<style>
</style>